Prop for mines.



PATENTEMAR.1o,1soa. F. yNEMEN 6 A. vom

APrLIdATloNf runnnov. 6.

g rately from pulverized waste bott-empiece has been put in place,

l mines which are made from artificial stone proved prop for mines .is shown by way of conipression."` 'l a casing b 'made-from any suitable waste ma- UNITED .ST

-FRIEDRIGH NELLEN AND ALBERT voler, or nssEN, GERMANY.

Pn'or non MINES.

To all whmmf'it may concern:

Be it known that we, FRIEDRICH NELLEN and ALBERT Voler, subjects of the German Emperor, residing `at Essen, Germany, have invented certain new and useful'lm rovements in Props for Mines, of Which t '1e following is a specification.'

The present invention relates to props for instead of being from Wood or iron as usual.v Theimproved props are very cheap and of great durability. y l

"In the accompanying drawings' the imexample.

Figures-i1 and 2 represent in-vertical Section tWo forms of the prop. Fig. 3 is another modifcation shown in vertical section. Fig. 4 is a detail view of the valve used in F ig. 2,- Which is represented on a larger scale.- Fig. 5 isa section on line a a: of Fig. 2.

The improved prop shown in Fig. 1 consists of a'hollow cylinder a which is closed at its lower end `through a bottom r having. an upper edge of coneshaped cross section, en-

tom end of the cylinder. p The lhollow cylintufa'ceous limestone or other suitable waste The cylinder is covered wit .1

terial, Such as shavings for example.

The' cylinder withits shell are manufactured inthe following manncr:--'l`he cylindei` d and its bottom piece l' are made sepastonc which is suitably'moistened andibrought into proper shape by pressure. The. shavings lfor the cover arestuck together with the ends and wound aroundl the cylinder which, after the is placed I pressed against the hanging-Wall,

on a spindle. The cover of shavings is made of the required' thickness and then 1m re i hated with a suitable substance to ren( er 1t l proof against fire 'and rot. The shavings are pressed on the cylinder by means of a press'- mg roller. The cover can be made of any other suitable material,such as pa er and the like. The inner Wall of the cy inder is smooth. The cylinder is filled with gravel Specification of Letters Patent. Patented March 10, 1908. Application ied November 6, 1907. i SeriaLNo. 400,973.

or Wastestone and a iston` c is placed upon the filling of the cylinder which is made from the same material as the cylinder and c'ovfered in asimilar manner With a cover land which has a large head. The pressure of the ground when the prop is used 'gradually comprlesses the filling f of the prop. Owing to t e on the prop the breaking of the Asame is prevented.

According to Fig. 2 the cylinder yis not filled with waste stone. The piston c is raised u to the hanging-wall of the lode by means o air under pressure which is suppliedy vto the cylinder through a valve g (preferably a non-returnvalve). yThis valveis .fixed in the bottom end 'of/the cylinder by meansv of a nut L.

piston.

When the piston is suiiiciently the valve g fradual increase of the pressure exerted A washer 'i at the lower end of the i ,y piston serves for securing the packing of the 1s automatically closed through the pressure exerted by the piston'.` According to F ig.

in dispensed with. The dimensions of the cy inder and the piston can cording to requirement. A W hat We claim as our invention'anddesire to secure by Letters Patent is:-

.An improved prop for mines comprising in the prop consists of a I ysolid cylinder c with coverfd, the'piston becombina-tion a hollow cylinder closed at the bottom and made from pressed waste stone,

a cover for said cylinder made from impre nateil shaving, a. piston in said cylinder ma e ,l from pressed Was-te' stone and provided with a cover made from shavings, and a suitable.

lilling of thel cylinder adapted to be com-` pressed bythe pressure exerted upon the pis# ton by the hanging-.wall of the lodefsubstantially as described and shown andlfor the purpose set forth.

ln testimony v hereof we have hereunto set our hands in presence of two subscribing w1 t messes. f

FRIEDRICH N ELLEN. ALBERT VOIGT. n 

